US STOCKS-Wall Street closes with a modest gains on Brexit deal, stimulus hopes

(For a Reuters live blog on U.S., UK and European stock
markets, click LIVE/ or type LIVE/ in a news window.)
* Brexit trade deal reached
* Stimulus package hits snag on Trump demands
* Indexes up: Dow 0.23%, S&P 0.35%, Nasdaq 0.26%

(Updates with closing prices)
By Stephen Culp
NEW YORK, Dec 24 (Reuters) - The S&P 500 ended higher at the
close of a shortened session on Thursday as investors headed
into the long Christmas weekend with hopes that an imminent
stimulus agreement, a Brexit deal, and the ongoing vaccine
rollout will spell brighter days in the coming year.
All three major U.S. stock indexes ended in positive
territory.
For the holiday-shortened week, the S&P 500 edged lower, the
Dow eked out a nominal gain and the Nasdaq advanced.
While stocks tend to perform well in the closing days of
December, a phenomenon known as the Santa Claus rally, the
resurgent pandemic and upcoming Senate runoffs in Georgia have
clouded the outlook this year. The U.S. House of Representatives blocked President Donald
Trump's attempt to change a $2.3 trillion coronavirus relief and
government spending package after Trump insisted on $2,000
direct payments to Americans. The move cast doubt as to whether the package passed by
Congress on Monday would be signed into law and raised the
threat of a partial government shutdown.
"If (stimulus) doesn't get passed in some form or another it
could mean severe consequences for the unemployed," said Peter
Cardillo, chief market economist at Spartan Capital Securities
in New York.
Britain reached a trade deal with the European Union after
months of negotiations, just days before leaving one of the
world's largest trading blocs. "(The Brexit deal) might be acting as a buffer for the
market in the sense that it's counteracting the negativity of
the stimulus bill being stalled," Cardillo added.
More than one million Americans have now been vaccinated
against COVID-19 even as the pandemic continues to rage in the
United States and political leaders moved to guard against a
more contagious variant of the disease sweeping across Britain.
The Dow Jones Industrial Average .DJI rose 70.04 points,
or 0.23%, to 30,199.87, the S&P 500 .SPX gained 13.05 points,
or 0.35%, to 3,703.06 and the Nasdaq Composite .IXIC added
33.62 points, or 0.26%, to 12,804.73.
Ten Of the 11 major sectors of the S&P 500 posted gains, led
by real estate .SPLRCR . Energy .SPNY was the lone loser.
Shares of Alibaba Group BABA.N dropped 13.3% on news that
China had launched an investigation into the company as part of
its antitrust crackdown. American Airlines Group Inc AAL.O said it was moving
forward with plans to recall furloughed workers, even as
forthcoming payroll protections, part of the stimulus package,
was called into doubt. Its shares dipped 1.4%
Moderna Inc MRNA.O said that it expects its coronavirus
vaccine to be effective against a new variant of the disease
discovered in Britain. Even so, its shares closed down 5.3%.
Altimmune Inc ALT.O slipped 9.3% after the U.S. Food and
Drug Administration issued a clinical hold on the company's
application to begin human testing of its single-dose COVID-19
vaccine, AdCOVID.
Advancing issues outnumbered declining ones on the NYSE by a
1.53-to-1 ratio; on Nasdaq, a 1.08-to-1 ratio favored decliners.
The S&P 500 posted 7 new 52-week highs and no new lows; the
Nasdaq Composite recorded 138 new highs and 5 new lows.
Volume on U.S. exchanges was 6.14 billion shares,
compared with the 11.30 billion average over the last 20 trading
days.